Lethan Corporation's Circuits Made Simple electricity exploration kit is a great way to introduce children to the fascinating world of electricity. This robust kit includes (5) 12-inch alligator clip connecting wires, (2) D cell plastic battery holders, (2) general purpose D batteries, (3) miniature light bulb holders, (1) jumbo knife switch and (10) miniature light bulbs. The plastic battery holders slide together in either series or parallel configuration. This simple circuits kit includes alligator clip wires for lightning fast connections. Don't waste your time stripping wires!